Clinical Features of Powered Wheelchair Users With

Clinical features of powered wheelchair users with

severely disabling multiple sclerosis

Lorraine H. De Souza PhD*, Andrew O. Frank FRCP

From Centre for Research in Rehabilitation, School of Health Science and Social Care, Mary Seacole Building, Brunel University, Uxbridge, Middlesex, UB8 3PH, UK (De Souza) and Stanmore Specialist Wheelchair Service+, Royal National Orthopaedic Hospital, Brockley Hill, Stanmore, HA7 4LP, UK (Frank)

*Author for correspondence:

Email:

Tel: +44 (0)1895 268847

Fax: +44 (0)1895 269853

+ Stanmore Specialist Wheelchair Service has now been disbanded.

Implications for Rehabilitation

1. Those with MS needing powered mobility should have a clinical assessment of their

MS, comorbid problems and complications of disability – including risks to health

and pressure ulcers.

2. Risks for osteoporosis, thrombo-embolic disorders and cardiovascular disease should

be included.

3. Weight management is essential and could be performed using weighing equipment

based in wheelchair services.

Abstract

Purpose: To describe the provision of electric powered indoor/outdoor wheelchairs for people severely disabled by multiple sclerosis and explore the complexities of comorbidities, clinical features and conditions secondary to disability influencing prescription.

Methods: Patients were recipients of electric powered indoor/outdoor wheelchairs (users) attending a specialist wheelchair service between June 2007 and September 2008. Electronic and case note records were reviewed retrospectively by a consultant in rehabilitation medicine. Data were systematically extracted under three themes; demographic, diagnostic and clinical profiles, and wheelchair factors and entered into a computer database. Further data were entered from the clinical records.

Results: Twenty eight men aged 57 (range 37-78, sd 12) years and 63 women aged 57 (range 35-81, sd 11) years with multiple sclerosis were reviewed a mean of 64 (range 0-131) months after receiving their wheelchair. Twenty two comorbidities, 11 features of multiple sclerosis and 8 conditions related to disability were thought to influence wheelchair prescription. Fifteen users were provided with specialised seating and 40 with tilt-in-space.

Conclusions: Findings suggest that the features of severe disabling multiple sclerosis

influence the prescription of the electric powered indoor/outdoor chair more than the

comorbidities. Assessment should include a health risk assessment.

Keywords: Multiple sclerosis, wheelchairs, comorbidity, disability, mobility, seating

Introduction

Multiple Sclerosis (MS) is an incurable long term debilitating neurological condition affecting predominantly young adults but may present in childhood and older age [1]. A recent report indicates that, for those with relapse-remitting MS, the median time from diagnosis to being wheelchair dependent (disability status scale (DSS) 8 [2]) is 28 years [3].

The most common functional consequence of MS is mobility disability which affects 50% of those diagnosed within 15 years of disease onset [4]. This is due to weakness, spasticity, balance problems and/or fatigue alone or in any combination [4]. However, it has been estimated from a Canadian survey, that approximately eight percent of people with MS (PwMS) will use powered wheelchairs [5].

Electric powered indoor/outdoor powered wheelchairs (EPIOCs) have been available through the UK National Health Service (NHS) for PwMS and those with other disabling conditions since 1996. Eligibility for NHS EPIOC provision requires a potential user to be able to control the EPIOC safely, independently, and be unable to walk around their home or self-propel [6]. These criteria are based on functional need and the potential benefit to the user.

For PwMS, EPIOCs will benefit those who cannot self-propel due to difficulty grasping and releasing the pushrim of a manual wheelchair, those who have asymmetry of upper limb power and/or wheelchair users’ shoulder [7] and consequently are unable to maintain speed over even short periods of time. This effort contributes to fatigue and is thought to render self-propulsion non-functional [8]. In addition to mobility disability, PwMS frequently have comorbidities that may affect treatment decisions [9-11]. The number of comorbid conditions are thought to increase with DSS and adversely affect health-related quality of life [12]. For example, the co-occurrence of pain and depression is thought to be noteworthy in PwMS [13], while older PwMS are known to be at increased risk of fracture [14]. Pain is a major problem for PwMS and a challenge for rehabilitation professionals [15] , particularly in their wheelchair use and seating [15,16].

Several symptoms characteristic of MS e.g. spasticity and fatigue are also relevant to wheelchair use. Studies of comorbidity in MS at onset of symptoms and at diagnosis have been reported and may be associated with differences in clinical characteristics [11]. The picture is likely to be very different in severe disabling MS due to disease progression and the impact of long-term physical and functional limitations for those who are wheelchair dependent. The challenge in this group of PwMS is in identifying what health issues are comorbidities as distinct diagnostic entities and what have arisen due to the long term impact of the disease. Thus deep venous thromboembolism (VTE) may be considered a separate diagnosis; however the increased frequency in late-stage MS is suggested to be due increased risk factors such as immobility and limb paralysis [17].

Little research has been carried out into the mobility needs of those who are very severely affected by MS. We have found no reports of comorbidity in wheelchair dependent PwMS. The benefits of independent powered mobility (PM) include education [6,18,19] or work [6,18,19] , and a range of social activities such as shopping [6,18,19] , church going [6,18,20], socialising with family and friends [6,18,20-22] and accessing healthcare facilities [6,20,21]. In addition, the increased mobility provided by PM enhances quality of life and wellbeing [22,23].

Multidisciplinary clinical teams assessing for prescription of EPIOCs will have knowledge and information about the potential users’ diagnoses. The important aspects of the clinical picture are those with significant implications for seating and/or the control of the EPIOC. Consideration needs to be given to the progression of the MS, the risk of potential complications including the development of new comorbidities e.g. osteoporosis or pressure sores, environmental factors and active ageing.

The aim of this study is to describe the provision of EPIOCs for people severely disabled by MS. We also aim to explore the constellation, and the complexities, of comorbidities, clinical features of MS and conditions secondary to disability influencing prescription. In doing so, we aim to compare our findings of comorbidity recorded in the clinic with the classifications used in self-report questionnaires in those mildly or moderately disabled with MS [9-11].

Methods

Potential participants were referred from their local wheelchair service. All individuals who had been prescribed an EPIOC and were currently using their chair were of interest to this study. Their electronic records were reviewed between June 2007 and September 2008 by a consultant physician in rehabilitation medicine and data were systematically extracted and entered into a computer database for analysis. Further data were entered from the clinical notes (charts) and all the data anonymised. Those relevant to this research were users with a diagnosis of MS.

Data were extracted under three themes; demographic profile, clinical profile and wheelchair factors. Demographic profiles consisted of information on age at initial EPIOC assessment and gender. Clinical profiles included the diagnosis of MS, comorbidities (e.g. asthma or cancer), features that reflected aspects of MS (e.g. trigeminal neuralgia or spasticity) and complications relating to the disability (e.g. pressure sores or (kypho)scoliosis). Comorbidities included all conditions reported by Marrie et al [11] and Horton et al [9] and were compared with Kang et al [10]. Conditions classified as comorbidities included those unrelated to MS but reported to have co-occurrence with the disease e.g. fractures [14] and pain [13]. Conditions classified as features of MS (e.g. trigeminal neuralgia, MS fatigue) were reported as known signs and symptoms of the disease [24]. Weakness was not recorded as it is universal in a group of EPIOC users.

Clinical features consequent to long-standing immobility and relevant to EPIOC prescription (e.g. pressure sores, shoulder pain, thrombo embolism) were classified as complications of severe disability. Back pain associated with kyphus or fracture was not coded as back pain but as the underlying cause. The following conditions were recorded as being probably painful: any form of spinal pain, osteoarthritis (OA), severe pain of uncertain cause, wheelchair users shoulder (WUS), shoulder pain, irritable bowel syndrome (IBS), trigeminal neuralgia (TN), polyarthralgia and spasticity.

Wheelchairs and seating

Data relating to specialised seating (SS), defined as ‘that which is needed by people who require a wheelchair but due to instability or deformity need additional support in order to function’ [25] were recorded. Other features included tilt-in-space (TIS), complex controls e.g. central joystick / tray mounted controls, head controls, switch controls, non-standard control system, interfacing with other assistive technology and cushions.

Methods of analysis

Data were analysed to describe proportions and frequencies of variables to determine the range and pattern of the wheelchair provided and medical factors recorded. Descriptive statistics were used to analyse demographic data and to describe subgroups of interest.

This study was approved by the National Research Ethics Service.

Results

Ninety one users had a diagnosis of MS. They consisted of 28 men aged 57 (range 37-78, sd 12) years and 63 women aged 57 (range 35-81, sd 11) years. Users had been with the EPIOC service a mean of 64 (range 0-131) months at the time of review. Only partial data were available on the medical profiles of 42 users whilst data on TIS was available for 82 users.

Twenty two comorbidities were identified. Of these, 12 were the same as those comorbidities found by Marrie et al [11] and Horton et al [9] (Table 1) and a further 10 were not represented in those publications. They were: fractures (n=6), cerebrovascular disease/stroke (n=2) (a noted comorbidity of Kang et al [10]), and one each of the following - amputation, cervical cancer, hearing impairment, lymphoma, platelet disorder, polyarthralgia, radial dysplasia and weight loss of uncertain cause. In addition 11 features of MS were found and 8 conditions consequent to disability (Table 2)

Thirty one users had no comorbidities, features of disabling MS or conditions consequent to disability (collectively referred to as additional clinical features – ACFs). Twenty nine users had one ACF and 31 users had two or more. A total of 41 different ACFs were noted. The frequency of ACFs in the remaining 60 EPIOC users totalled 108, of which 42 were comorbidities, 28 were disabling features of MS and 38 were conditions consequent to disability (Table 2).

The most frequent comorbidities found were asthma and depression. Poorly controlled spasticity was by far the most common feature of MS noted in 10 users. Pressure sores including leg ulcers and low back pain were the most often found conditions consequent to disability (Table 2). Forty one painful conditions were experienced by 31 users. The most common causes of pain were low back pain and spasticity.

Wheelchairs and seating

Fifteen users (eight men) were provided with SS and 40 (14 men) with TIS. Only seven users were given both SS and TIS. Of the 15 users with SS, 11 had one or more ACFs (Table 3) and eight had painful conditions. Of these 15, three needed matrix seating systems, and the remainder had standard pressure-relieving cushions (Roho=3 [The Roho Group, Belleville, IL USA], Vicaire=3 [The Comfort Company, Bozeman, MT USA], Qbitus=3 [Qbitus Products, Halifax, UK], Jay2=2 [Sunrise Medical Limited, West Midlands, UK], TempurMed=1 [Sumed International (UK) Ltd, Glossop, UK]).

Of the 40 users with TIS, 34 had one or more ACFs (Table 3). Twenty eight had standard pressure-relieving cushions (Qbitus=15, Roho=3, Vicaire=3, Jay2 and V-Trak [Pontyclun, Rhondda Cynon Taff, UK] two each and one each of Jay-Active, Transflow [Karomed Limited, Chard, UK] and Protech [Invacare UK, Bridgend, UK]). Two users were given matrix seats and six had standard wheelchair seats whilst there was no data on four cushions.

Of the 31 users with problematic pain, only 14 used TIS and eight used SS. Only two users required complex controls. A 50y old woman with secondary progressive MS and hyperthyroidism had profound finger/hand weakness challenging our control system. She needed a non-standard tray-mounted system that interfaced with an environmental control unit (ECU). The other was a 62y old man with MS as the only diagnosis who needed SS and chin controls. This user was advised to have an additional control stick for carer's use.

None used wheelchair mounted ventilators. Of the 10 users with poorly controlled spasticity, six received either TIS and or SS. Both users with severe MS fatigue had TIS.

Safety concerns were noted in six users. Three had suffered accidents through toppling out of their EPIOC (one had driven off the curb). One experienced an electric burn on the arm following an electrical short from the control system through the user’s metal jewellery. The user noted above (with carer-operated controls) was given these controls for safety reasons e.g. when the user was weaker following an infection or flare in the MS. Another had the EPIOC withdrawn following symptom progression resulting in an inability to drive safely.

Discussion

This paper reports, for the first time, the clinical features seen in EPIOC users severely disabled by MS that are due to both the established impact of late stage MS and the accumulative effect of long-term disability. Our results demonstrate that these features, including comorbidity, in PwMS severely affected by mobility disability are very different when compared with those at diagnosis.

Comorbidities

A comparison of our results with published MS comorbidity [9-11] shows 12 conditions that have previously been reported but 10 that are unreported in the current literature. Many possible explanations for this discrepancy relate to the later course of the life cycle that severely disabled PwMS reflect, which also allows for the treatment of some of these conditions to have been completed e.g. cataracts. Other PwMS may have died at earlier stages of the disease due to related/unrelated conditions. The apparent under-reporting of published MS comorbidity may be due to our smaller group of PwMS. Nonetheless comorbidities found in our group e.g. cervical cancer and lymphoma are not reported

Comorbidity is associated with increased disability in MS [11] and is also associated with differences in clinical characteristics of the disease [11]. It is recognised that complications due to MS, or its disabling consequences e.g. thrombo-embolism or choking, and nonneurological comorbidities e.g. cardio-respiratory conditions, are causes of unexpected deaths [26]. Our results include these and other potential risks of premature death. Evidence is lacking to support the difficult clinical decisions needed to inform best rehabilitation practice for those with multiple health conditions [27] but it is recommended that taking specific precautions could prevent some deaths in MS [26].